When a server is used for providing stable services to the users through the network, the response time of the server sometimes increases. Such an increase in response times of the server might occur many times a day.
The causes of increase in response times include external causes due to variations in the external traffic, and internal causes resulting from the internal program structure. If the cause of increase in response times is an external cause, it may be possible to prevent an increase in response times by increasing the hardware resources, such as by increasing the number of servers and by controlling the traffic. On the other hand, if the cause of increase in response times is an internal cause, it may be possible to prevent an increase in response times by modifying the configuration of the software, for example.
In this way, the way to handle an increase in response times differs depending on whether the cause of increase is an external cause or an internal cause. That is, if it is possible to determine whether the cause of increase is an external cause or an internal cause at an early point, the response time of the server may be improved promptly.
As a method for identifying these causes, a “drill-down” approach is often used that observes the behavior in a short period time in detail. However, this drill-down approach is performed manually, and therefore is not efficient.
There have been various methods for analyzing the performance of a server using a computer. For instance, an analysis method has been disclosed that analyzes the responsiveness of a computer system including a plurality of servers (see, for example, International Publication Pamphlet No. WO2006/046297).
However, such a related-art method of analyzing the server performance using a computer is not designed to efficiently analyze the cause of increase in response times so as to determine, for example, whether the cause is an internal cause or an external cause. Accordingly, an analytical determination is still performed manually using a drill-down method at an early stage of the analysis, and therefore it takes time to identify the cause of increase in response times. As a result, it is difficult to quickly improve the response time of the server.